Technical Field
The present disclosure relates to surgical instruments and, more particularly, to an endoscopic surgical forceps configured for treating and/or cutting tissue.
Background of Related Art
A surgical forceps is a pliers-like device which relies on mechanical action between its jaw members to grasp, clamp, and constrict tissue. Typically, at least one handle or lever is used to open and close the jaw members, and to provide compression force on tissue between the jaw members, to lock the jaw members in a closed position, and/or to apply energy to the jaw members to seal the tissue disposed therebetween.
Generally, such handles and levers used on surgical instruments are one of two types. One type is a simple pivoted handle that provides a near constant mechanical advantage throughout its stroke, and which is useful in many surgical situations. The second type of handle includes an additional link to provide a geometrically increasing mechanical advantage toward the end of its stroke to help provide the force necessary to compress tissue.
Both of these types of handles fix the mechanical advantage of the drive system such that the drive system cannot be optimized independently over the entire lever stroke. Often times, it may be desirable for a system to include fine dissection capability (a relatively large amount of handle travel for a relatively small amount of jaw member movement) when the jaw members are in an initial, or open position, and to include a high mechanical advantage while applying compression force to tissue disposed between the jaw members when the jaw members are in or near their approximated position (to help reduce surgeon fatigue, for instance). However, current handles are generally unable to achieve both of these desires in a single system, thus resulting in a compromised result.